Improvement



'UNITED STATES PATENT QFFIGE?.

EDWIN SUMNER, OF BALDWINSVILLE, MASSACHUSETTS.

IMPROVEMENT `lN PULP-ENGINES.

Specification forming part of Letters Patent No. 191,898, dated J une 12, 1877 application filed Y November 11, 1876.

To all whom it may concern:

Be it known that I, EDWIN SUMNER., of Baldwinsville, inthe county of Worcester and State of Massachusetts, have invented a new and Improved Mixer for Paper-Pulp Engines and I do hereby declare that the following is 3 and 4 are, respectively, side, end, and top views of the mixing device.

My improvement consists in arranging within the roll-cover or. hood of a paper-pulp engine, an inclined chute that receives the pulp thrown up by the roll, and carries it transversely toward the outside of the curb, the object being to equalize the Velocity of the circulation ofthe pulp in the curb, so that a homogeneous mass of paper-pulp is produced. In the drawing, A is the curb of a paperpulp engine, and B is the grinding-roll of the engine. U is the back-fall, and D is the hood for the roll. E is the midfellow or middle partition of the curb. F is a crossbar that rests upon the midfellow E, and upon the outer Wall of the curb near the cover D. Gr is an inclined chute, supported by the bent bars a a, which are attached to the cross-bar F. This chute consists of a plank, H, and backpiece I. Its wider end abuts against the midfellow E, and it extends toward the outer wall of the curb, and is inclined downward, so that the pulp delivered to it runs toward its outer and narrower end. The back piec'e I is attached to the bars c c, and extends about halt' way to the outer Wall of the curb. and prevents the pulpfrom running off in that direction. rIhe plank H inclines -down- Ward and backward ytoward the back-piece I.

In paper-pulp engines of the ordinary construction, to which my invention is to be applied, and which is best shown in plan view in Fig. 5, it will be seen that the pulp circulates around the midfellow and inside the curb. Incident to this circulation, certain ob'- jections exist as follows: The portions of pulp adjacent to the midfellow have a shorter path in circulating than the portions of the pulp adjacent to the curb, or near the outside, and consequently the pulp next to the midfellow passes undergthe roll oftener, and is ground ner than that next to the curb. Furthermore, the thicker and heavier portions of the pulp or stock, in turning the bends at the ends are, from centrifugal action, thrown outwardly to the curb, while the thinner and more watery portions of the pulp wash rapidly around close to the midfellow. This still further prevents the homogeneous reduction ofthe pulp, by increasing the speed of the pulp next to the midfellow, and diminishing that of the pulp next to the curb, which not only involves the same objection of grinding the inner pulp finer than the outer pulp, but also prevents the best action of the engine. These objections have been attempted to be removed by the stirring and mixing of the pulp by paddles in the hands ofan attendant., but this method is not automatic, and is imperfect and unsatisfactory.

In the operation of my device, the roll, re-

volving at a high rate of speed, dashes up the more liuid pulp upon the inclined chute G, whence it rushes outwardly toward. the curb and drops off the narrow end 4of the saidV chute upon the outside pulp adjacent to the curb. The effect produced is as follows: The inner portions of the pulp next to the midfellow, which have a tendency, as before described, to grind finer, are dumped into the pulp near the outside, which is not ground so fine, by reason of its longer path, and consequently the pulp is more homogeneously mixed and ground. In addition to this result,

also, thereis another of importance.

se'en that the mixing of the pulp is made automatic and continuous, the movement of the outside pulp is accelerated, and the pulp is ground in a uniform and homogeneous mass instead of in different grades.

Having thus described my invention, 'what I claim as new is- In a paper-pulp engine, thel combination with the grinding-roll, the curb A, 'and the midfellow E, of an inclined transversely arranged chute, adapted to receive the watery pulp thrown up by the lroll, and to eeot a homogeneous mixture of the stock, substantially as described, and for the purpose set forth.

EDWIN SUMNER.

Witnesses tv Fn'ANos 'KET'.rY, H. M. SMALL. 

